[Diagnosis of cholestatic disorders]

Cholestasis is known as an etiologically diverse clinical entity which requires a broad differential diagnostic workup. In the majority of patients, history, clinical examination, clinical chemical analysis, and abdominal ultrasound enable the differentiation between extrahepatic and intrahepatic cholestasis. This review summarizes our current knowledge in the diagnosis of cholestatic disorders.

In regard to clinical practice, diagnostic tools and new developments in imaging and molecular genetics are discussed including an algorithm for the diagnostic workup of cholestatic patients.

Ultrasound and computed tomography have represented the most important primary imaging techniques in hepatobiliary disorders over the last 2 decades. The direct visualization either by endoscopic retrograde cholangiopancreatography (ERCP) or percutaneous transhepatic cholangiography (PTC) still remains the gold standard in the evaluation of the extrahepatic bile duct. In the past decade, magnetic resonance cholangiopancreatography (MRCP) has increasingly been established as a noninvasive alternative, thereby reducing the necessity of ERCP as an invasive exploration of the biliary system. Liver biopsy is indicated for the histologic grading and staging of intrahepatic cholestatic disorders. Recently, molecular genetic studies have elucidated several mutations in genes of hepatobiliary transporters which are responsible for hereditary forms of cholestasis in man. Thus, molecular genetics may be of interest in single cases of unclassified cholestasis or familial syndromes and will contribute to the routine diagnosis of hereditary cholestatic syndromes in the future. In summary, application of these diagnostic tools will finally lead to an unequivocal diagnosis in the majority of cholestatic patients with consecutive rational therapy.